Korean Ocean Research and Development Institute

About: Korean Ocean Research and Development Institute is a facility organization based out in Busan, South Korea. It is known for research contribution in the topics: Sea surface temperature & Gene. The organization has 1770 authors who have published 3032 publications receiving 50142 citations.

FrsA functions as a cofactor-independent decarboxylase to control metabolic flux

Abstract: The interaction between fermentation-respiration switch (FrsA) protein and glucose-specific enzyme IIA(Glc) increases glucose fermentation under oxygen-limited conditions. We show that FrsA converts pyruvate to acetaldehyde and carbon dioxide in a cofactor-independent manner and that its pyruvate decarboxylation activity is enhanced by the dephosphorylated form of IIA(Glc) (d-IIA(Glc)). Crystal structures of FrsA and its complex with d-IIA(Glc) revealed residues required for catalysis as well as the structural basis for the activation by d-IIA(Glc).

Review on observational studies of western tropical Pacific Ocean circulation and climate

Abstract: The Western Tropical Pacific (WTP) Ocean holds the largest area of warm water (>28°C) in the world ocean referred to as the Western Pacific Warm Pool (WPWP), which modulates the regional and global climate through strong atmospheric convection and its variability. The WTP is unique in terms of its complex 3-D ocean circulation system and intensive multiscale variability, making it crucial in the water and energy cycle of the global ocean. Great advances have been made in understanding the complexity of the WTP ocean circulation and associated climate impact by the international scientific community since the 1960s through field experiments. In this study, we review the evolving insight to the 3-D structure and multi-scale variability of the ocean circulation in the WTP and their climatic impacts based on in-situ ocean observations in the past decades, with emphasis on the achievements since 2000. The challenges and open questions remaining are reviewed as well as future plan for international study of the WTP ocean circulation and climate.

Distribution and origin of shallow gas in deep-sea sediments of the Ulleung Basin, East Sea (Sea of Japan)

Abstract: A synthesis of high-resolution (Chirp, 2–7 kHz) subbottom profiles in the Ulleung Basin reveals patchy distribution of shallow (<90 m subbottom depth) gassy sediments in the eastern basin plain below 1,800-m water depth. The shallow gases in the sediments are associated with acoustic turbidities, columnar acoustic blankings, enhanced reflectors, dome structures, and pockmarks. Analyses of gas samples collected from a piston core in an earlier study suggest that the shallow gases are thermogenic in origin. Also, published data showing high amounts of organic matter in thick sections of marine shale (middle Miocene to lower Pliocene sequence) and high heat flow in the basin plain sediments are consistent with the formation of deep, thermogenic gas. In multi-channel deep seismic profiles, numerous acoustic chimneys and faults reflect that the deep, thermogenic gas would have migrated upwards from the deeper subsurface to the near-seafloor. The upward-migrating gases may have accumulated in porous debrites and turbidites (upper Pliocene sequence) overlain by impermeable hemipelagites (Quaternary sequence), resulting in the patchy distribution of shallow gases on the eastern basin plain.

High density culture of the freshwater rotifer, Brachionus calyciflorus

Abstract: The freshwater rotifer, Brachionus calyciflorus is one of the live food organisms used for the mass production of larval fish. In this study possibility of obtaining high density cultures of the freshwater rotifer B. calyciflorus were investigated. The two culture systems used differed in their air and dissolved oxygen supplies using three temperatures in each case: 24, 28 and 32 °C. Rotifers were batch-cultured using 5 1-vessels and fed with the freshwater Chlorella. The growth rate of rotifers significantly increased with an increase in temperature. The maximum density of the rotifers with air-supply at 24 °C, 6500 ind. ml−1, was significantly lower than those cultured at 28 and 32 °C, i.e. 8600 and 8100 ind. ml−1, respectively. Dissolved oxygen levels decreased with time and ranged from 0.8 to 1.4 mg 1−1 when the density of freshwater rotifer was the highest at each temperature. The highest density (19 200 ind. ml−1) of freshwater rotifer was obtained in cultures with a supply of oxygen at 28 °C. Densities of 13 500 and 17 200 ind. ml−1 were found at 24 and 32 °C, respectively. Levels of NH3−N increased with time and a dramatic increase of NH3−N was observed at high temperatures. Levels of NH3−N at 24, 28 and 32 °C were 13.2, 18.5 and 24.5 mg 1−1, respectively. These levels coincided with the highest rotifer density at each of the three temperatures. When rotifers were cultured with an oxygen-supply and pH was adjusted to 7, the maximum density of rotifer reached 33 500 ind. ml−1 at 32 °C . These results suggested that high density culture of freshwater rotifer, B. calyciflorus could be achieved under optimal conditions with DO value of exceeding 5 mg 1−1 and NH3−N values of lower than 12.0 mg 1−1.